The invention relates generally to medical imaging and, in particular, to the identification of different anatomical and/or pathological structures in medical images.
Non-invasive medical imaging technologies allow a caregiver to obtain and view images of the internal structures and organs of a patient without performing surgery or other invasive procedures. In particular, technologies such as X-ray radiography, computed tomography (CT), tomosynthesis, magnetic resonance imaging (MRI), ultrasound, C-arm angiography, positron emission tomography (PET), and single positron emission computed tomography (SPECT) use various physical principles to create two-dimensional and/or three-dimensional representations of the interior of the human body. For example, in those imaging modalities utilizing X-rays, the principle of operation typically involves assessing the differing attenuation of the X-rays by the patient's body at one or more angles. Based upon the differential attenuation attributable to different tissues, a two- or three-dimensional image may be reconstructed that accurately depicts the internal structure of the patient. Different imaging modalities apply differing physical principles, but in each case a useful image derived using some property of the patient's body is produced.
To utilize some of the imaging modalities or to image certain anatomic regions, a patient may be treated prior to imaging to improve the image quality. For example, as part of the process of acquiring CT images of the colon, the patient may undergo catharsis, or colon cleansing, to cause the expulsion of the contents of the colon. In addition, the colon may be inflated or pressurized with air. These processes are very uncomfortable to the patient and may result in the patient not complying with the periodic screening schedule recommended for the patient. As a result, the patient may not be screened as frequently as recommended. Likewise, the imaging protocols for other organs may be similarly uncomfortable and may discourage or prevent patient compliance with the appropriate examination schedule. Therefore, it may be desirable to reduce or eliminate the uncomfortable preliminary steps involved in imaging various organs.